Carburetor



Oct. 9, 1928.

C. F. JOHNSON CARBURETOR May 5,

gmxmtoc -1 controlled. a

- This inventlon consists -in a carburetmg' o carbureting chwannabe-9.192s

UNITED STATES,

r. Jonson, or nrrnorr, '1

A E T lC .-k-

invention relates to carburetors for internal combustion engines formotor cvehicles which carburetors are provided with ofiset fuel chambersand fuel nozzles or assages extending abovethe level of the e1 therein,and its object is to provide an-apparatus of this character'in which theheavy particles of; fuel will be intercepted and in which the richnessof the fuel may be closely deviceha'ving an outlet passage of standardsizeextending from the carbureting chamv ber in which the throttle valveis mounted,

the net cross-sectional area ofthe carbureting chamber'at the throttleshaft being equal to that of the outlet opening, and the carburet devicehaving a shoulder at the plane where the discharge passage, connects tothe am r.

It also'consists in the details of construction illustrated in theaccompanying drawand particularly pointed out in the aims.

In the drawing, Fig.1 is a side elevation of a carburetor embodyingthisinvention.

'Fi 2 is acentralvertical section thereof,

imilar reference characters referto like parts throughout the severalviews.

The bod of he carburetor is formed with e gassage 2, a float chamber 3,a

an air-int mixin cham er 4 in which is mounted a "throttle valve 5on-ashaft 6 and a .fuel outlet. passage 7 surrounded by a flange 8. -Theflbat chamber has afmovable cover 9' and a float 10 therein attached tothe lever 12. Screwed intothe top of thefloat chamber is l a sleeve 13which is providedwith a seat (not shown) for a valve 14 of any wellknown designtila small chamber 15 being mounted on e upper portion 16ofthis sleeve and having a fuel sup 1y connection 17. The screw 18 holdsthis 0 amber 15 and the fuel screen 19 in position. A wall 23 separatesthe, air passage2 from the float chamber. This construction .forms no.part of the present invention.

A fuel passage 20 extends along the botconsisting with the' fuel nozzle.

m1. sis-151' is new.

seldom over thirty-. vehicle can negotiate, without the fuel flowfrom.the top of-theno'zzle. This w 1 be. less than that-of the'lin'eIX-QdrawninFig.2.

The. nozzle extends of a collar wardly" tapering p a flange 30, whichposts \32 connected a 33'. Slidable b on the collar 28 and 32 is an airvalve consisting of a cylinder 34 and perforated top '35. .Depending .36having a' central opening 37 in hlinement K stem 38 is slidable helddownby the "spring 39 and this stem connects (to a valve 40 slidable onthe fuel nozzle 27. An arm '41 on the outside of the air-intake passageconnects to the arm 42 within this passage and this second armcxtendsbeneath the curved upper end of the stem 38. Substantially no air canthrough the space between the nozzle and the inner wall of the valve 40.

The fuel outlet passage -7 is smaller in diameter than that portion 43of themixing .chamber 4 through which *the shaft 6' ex-..

tends, so that this lower portion 43 will have. .as large anefiectivearea as the outlet 7..-

I have found that a carburetor has greater fuel capacity when the areaoiE-the. assage by the throttle shaft 6 is as large as to area of theoutlet 7. This outlet 7 could be bored out to the same diameter as isthe passage 43 without loss offuel capacity, but the industries havestandardizedthe size of the outlet flange 8 of the different sizesfofcarburetor, and it is, therefore, not practical to properly match suchbored out carburetors to the standard and besides, they would w be quite.likelyto leak air at these improperly'made joints.

I also have'foundat certain low speeds, on some motors, a decidedmcrease of power can. be obtained' by. use of the annular shoulder 44,and that this advantage is se {which the motor I up into. theventuri 428 having. a down- 29 which ends at is supported by the from the'top'isahub thro h the bottoni' of the air-intake p an isnormally ate, and

cured by having this shoulder at substantially any point between thethrottle and the oint gwhere the intake manifold branc es. The probablereason is that the heavy fuel globules strike against this shoulder 44and are broken up. 1

The opening within the flange 30 may be closed by the top of the spool40 when that I reached.

claims.

is slid u byithe arm 41,'which reduces the air sup y which mayflow uparound the nozzle 2 and creates a greater suction at the dischargeend ofthe fuel nozzle; In other words, the usual choke action is obtained .byswinging the arm 41. The air valve 34 re-' mains in its normal positionand forces all the air to pass through the aperture in'the the nozzle solong as i flange and aroun the engine is running-at moderate s eds, butwhen the throttle 5 is opened sufficiently to cause enough suction tolift the airwvalve, the air will in part flow 'out laterall between theposts, 32 and not pass the disc arge end of the fuel nozzle. This willcause the explosive mixture tobecome much leaner for the higher speedsof the engine.

. Accidents have occurred because of light farm tractors'tipping .overbackward when 20- -pulhng on mired lows and other heavy loads, thetractor wieels standing still and the niacliine simply windingitself uparound I the axle.- To prevent this the intake 21 of the fuel passage'20 is'so positioned that when the carburetor is inclined until the lineX--X of Fig. 2 is horizontal, the'intake 21 will be entirely above thisline. This line indicates approximately the f el level when thecarburetor is thus tilted and is a greater angle than the steepest hillthevehicle can climb. But this angle hardly half that V at which :thetractor fig:- over backward,

and'as the upward swin of the vehicle is always slow, the fuel supply tothe-engine is cut off before the dangerous angle-is The details ofconstruction and the proportions of the ,several parts'of thiscarburetor may allbe varied by those sln'lled in 40 the art withoutdeparting from the spirit of my invention as set forth in thefollowing 1. In. a carburetor, a carburting chamber and a ring at thelower .end thereof, a plurality of posts extending upward from said,ring and a collar at the upperends of theposts, said collar having adownwardly tapering central vpassage and an inwardl extendin flan e atthe lower end thereo an air va ve shdable on the collar'and comprising acylindrical shell fitting around the collar and posts and aperforatedhead at the upper end ofjthe shell, :1 fuel nozzle ex- .tending upwardabove the flange inthe colthe fuel nozzle to reduce' the effective open--1ng in said collar. 4 Y 2. In a carburetor, in c n; 1binat1on,.a fuelmixture outilet passage, a mixing chamber,

in the mixing chamber theeffective cross sectional area of said mixing:chamber at thethrottle shaft being substantially the" same as that ofthe fuel mixture outlet passage, said carbliretor being formed-with anannular shoulder extending at substantially. right angles to theflo'w ofthe fuel mixthe, nozzle'and adaptedto vary theefl'ective area of saidcentral passage, andmeans' controlled by the flow of air throu h thecentral passageito regulate the ow of air through said radial assa vCHES lar, and a second'valve slidable relative to a at a circular p atethrottle'and a shaft therefor ges. R F. JOHNSON. I

